Chelsea Football Club owner Roman Abramovich is "good at appearing to be humble", a High Court judge was told today.

Russian oligarch Boris Berezovsky - who says he was "betrayed" by Mr Abramovich following an oil firm deal and is claiming billions of pounds in compensation - said the billionaire Russian businessman was "good at getting people to like him" and "good at psychology".

Mr Berezovsky, 65, says Mr Abramovich "intimidated" him into selling shares in Russian oil company Sibneft at a fraction of their value.

He is claiming more than £3 billion in damages from Mr Abramovich - and alleging breach of trust and breach of contract - in a trial in the Commercial Court in London.

Mr Abramovich, 44, denies the allegations, disputes that "oral agreements" were made and denies Mr Berezovsky is entitled to damages.

Mr Berezovsky today started giving evidence to judge Mrs Justice Gloster as the trial, expected to last more than two months, entered its fourth day. Mr Abramovich watched from the public gallery.

"He (Mr Abramovich) is good at getting people to like him and good at psychology in that way," said Mr Berezovsky in a written witness statement given to the judge.

"He is good at appearing to be humble. He is happy to spend days just socialising with important or powerful people if that is what is needed so he can get closer to them."